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A305431 Restricted growth sequence transform of A278222(A305295(n)), constructed from runlengths of 1-digits in base-3 representation of A245612(n). 4
1, 2, 1, 1, 3, 4, 2, 3, 4, 1, 3, 1, 1, 2, 1, 2, 5, 6, 2, 7, 8, 4, 2, 1, 3, 7, 1, 4, 7, 7, 1, 1, 9, 1, 7, 10, 1, 11, 1, 2, 12, 8, 5, 7, 1, 1, 2, 8, 4, 7, 1, 7, 7, 8, 3, 2, 8, 7, 1, 7, 7, 1, 2, 1, 13, 14, 7, 11, 6, 1, 12, 14, 3, 11, 8, 8, 7, 15, 1, 16, 10, 17, 3, 17, 16, 3, 1, 15, 3, 1, 7, 7, 1, 1, 7, 6, 5, 7, 6, 1, 7, 11, 1, 8, 8, 1 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,2
LINKS
PROG
(PARI)
A003961(n) = my(f = factor(n)); for (i=1, #f~, f[i, 1] = nextprime(f[i, 1]+1)); factorback(f); \\ From A003961
A048673(n) = (A003961(n)+1)/2;
A254049(n) = A048673((2*n)-1);
A245612(n) = if(n<2, 1+n, if(!(n%2), (3*A245612(n/2))-1, A254049(A245612((n-1)/2))));
A289813(n) = { my (d=digits(n, 3)); from digits(vector(#d, i, if (d[i]==1, 1, 0)), 2); } \\ From A289813
A005940(n) = { my(p=2, t=1); n--; until(!n\=2, if((n%2), (t*=p), p=nextprime(p+1))); t };
A046523(n) = { my(f=vecsort(factor(n)[, 2], , 4), p); prod(i=1, #f, (p=nextprime(p+1))^f[i]); }; \\ From A046523
A278222(n) = A046523(A005940(1+n));
rgs_transform(invec) = { my(om = Map(), outvec = vector(length(invec)), u=1); for(i=1, length(invec), if(mapisdefined(om, invec[i]), my(pp = mapget(om, invec[i])); outvec[i] = outvec[pp] , mapput(om, invec[i], i); outvec[i] = u; u++ )); outvec; };
v305431 = rgs_transform(vector(65538, n, A278222(A305295(n-1))));
A305431(n) = v305431[1+n];
CROSSREFS
Cf. also A305301.
Sequence in context: A286510 A336842 A159933 * A128314 A025564 A052265
KEYWORD
nonn
AUTHOR
Antti Karttunen, Jun 01 2018
STATUS
approved

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Last modified March 28 14:38 EDT 2024. Contains 371254 sequences. (Running on oeis4.)